Clusters, Gauges, Speedo & Odo meters (1 Viewer)

[bj40man]

I have been reading the 20+ pages on this thread and quite frankly this is amazing!! My highest regards for those brilliant minds behind these threads! Im so tempted to go mess with my cluster after having seen all this.

I was looking in the posts of this thread to see if this question has been asked, but didn't find it, so here it goes:

I have a US Specs 1971 FJ40 with a transplanted b diesel engine. All else the same, and have always been intrigued at the amp meter (only instrument currently working - or so) because it wobles back and forth like crazy through all the spectrum of the dial rendering it useless for accuracy purposes.

Do any of you have a clue why this could be happening? The diagram looks very simple! Now on my 1975 BJ40 the instrument works like a charm.

Thanks!

 

[bj40green]

I have been reading the 20+ pages on this thread and quite frankly this is amazing!! My highest regards for those brilliant minds behind these threads! Im so tempted to go mess with my cluster after having seen all this.

I was looking in the posts of this thread to see if this question has been asked, but didn't find it, so here it goes:

I have a US Specs 1971 FJ40 with a transplanted b diesel engine. All else the same, and have always been intrigued at the amp meter (only instrument currently working - or so) because it wobles back and forth like crazy through all the spectrum of the dial rendering it useless for accuracy purposes.

Do any of you have a clue why this could be happening? The diagram looks very simple! Now on my 1975 BJ40 the instrument works like a charm.

Thanks!

Hi bj40man,
Your problem is caused by a defective VR (Voltage Regulator). The OEM VR regulates the charging in 3 steps. Full charge, Trickle charge and No charge. Sometimes/often an aftermarket VR is used (by a PO?) that only does 2 steps, charge and no charge. This causes the Ammeter to go crazy when the battery is fully charged (and the VR goes to no charge and immediately kicks in and start charging again.
Or...... the VR that you have is malfunctioning and way to critical and is "flipping" between positions.
More info in this thread: -► Voltage Regulator (ext.) / How it works
VR's are not expensive, replace it or change it out with your other Cruiser and see what happens.

Rudi

 

[bj40man]

Thank you for your prompt response! It makes total sense. The VR on this cruiser was replaced for a solid state unit not long ago. I have a third one (a troopie) which works on 12v, for the BJ is 24v, and also has a solid state unit, It is a 1980 model and the AMP meter doesn't work. Will try to swap them to see what happens.

Take care!

 

[bj40green]

From Jan 1979 the whole Ammeter circuit changed. The way the current was measured and the Ammeter changed into 50-0-50.
Due to factors unknown (or bad design) the Ammeter showed only a tiny movement.
In this thread (a few pages back) you'll find the solution by replacing a fusible link to get the Ammeter working.

Rudi

 

[Dagha Boy]

Hi Rudi. A quick note to thank you for the incredible stuff you have posted here. I found it yesterday when I decided to tackle refurb of a 1977 HJ45 cluster. I got it all stripped down nice and easily with the help of your and BAAS' threads. I would NEVER have found the clip on the high beam lens on my own.

The cluster I am working on was on a farm vehicle, used hard and uncared for all its life. From what I could see the cluster had never been opened, (even the light globes are all still the Yazaki brand. What struck me as strange though is that the 30-30 ammeter is not a Yazaki. Given the vehicles history I doubt that it would have been replaced if it became defective at any point. It appears to be identical in all respects to the Yazaki gauge, but for no Yazaki branding on the face, and the face is held on by two screws instead of rivets. It has no manufacturers' markings on it, but for an "OK" stamp on the back of the face. The Yazaki gauges have nothing on the back of the face plates.

GAUGES IN PLACE.

FRONT FACE

REAR SHOWING QC (?) STAMP

Just what may be an anomaly and may explain something to somebody down the line perhaps. Oh, the other thing, the nuts on the back of this gauge required an 8 wrench and the Yazaki ones a 7... another indication to me that it is probably not a Yazaki, even if it appears to have been original fit.

With mine all stripped down, everything seems to look ok at first sight but for the circuit board. It appears to me that the printed circuit for no1 - ground - has "melted" off. I'm in the bush so don't have testing equipment to test all these gauges. I do know that the oil pressure gauge worked, nice and high on a cold engine and then zero once the engine heats up. Tells me the gauge is fine but the engine not...

CIRCUIT BOARD (This is not very clear but if you look carefully you can see what I think is a break on the no1 circuit.)

The question is: How does one repair a break like this?

Once again, thank you very much Rudi for so selflessly sharing your incredible knowledge with us.

 

[bj40green]

The studs on the Ammeter are bigger because of the amount of current that flows there.
The Ammeter circuit is also separate from the other gauges for the same reason.
That Ammeter is OEM, don't worry about that.

The question is: How does one repair a break like this?

Pin 1 is part of the Ground circuit. The cluster is grounded by the 2 screws and via Pin 1. This track is needed when you test the cluster out of the dash.
Looks like a piece of copper track is missing (evaporated) and that somebody already removed the blue protective coating.
The solution:....... Solder a piece of wire over the gap.
Here is an example of a cluster with 4 repairs. 3 blue wires and 1 red.

That cluster is in a very good condition. Beautiful.

Rudi

 

[Dagha Boy]

Thanks Rudi. What time is it your side - about 01:00? you're either up late or up early.

Thanks to your thread I of course already know exactly how to go about doing the actual soldering!!!

Reading your stuff is really like doing a study course via the internet.

The cluster is in good nick, but showing tiny bits of rust on the edges and ledges where the dust gathers. I would have liked to do a proper job but I understand that the only lettering available costs about $100. Our currency value has lost roughly 50% over the past 18 months, so that is a little too rich for my blood at the moment.

Something you probably know (but I have not seen it specifically dealt with anywhere) is the role dust seems to play in rust formation. I have noticed that everywhere, from the chassis frame to the instrument cluster, an accumulation of dust, no matter how small, always goes with rust underneath. I imagine that when the humidity gets high, the dust becomes damp and holds the moisture allowing the rust to flourish.

My planned solution to this for the cluster is to seal it all up very well when reassembling to keep the dust out and to place a couple of those little packets of silica stuff inside to keep the air inside dry. Who knows, maybe that will help to stave off the rust in future. If not, nothing lost.

Again many thanks for your sharing and assistance.

 

[bj40green]

Thanks for all the praise.
When you reassemble the cluster.... do it in an air conditioned space where the humidity is low.

BTW it's now midnight and yes, I'm a late sleeper.

 

[Racer65]

Rudi, ever since I started selling the 12V cluster in my store, people have been regularly asking if I have a 24V cluster available. I don't believe it's available new; however, you stated that a 24V cluster is a 12V cluster with a resistor in the back and 24V bulbs. Is it straightforward to convert a 12V cluster to a 24V one? If so, which parts should be used? Thanks in advance.

 

[pbgbottle]

The circuit board is different. And it uses the resistor also to jump two sections of the board together. I converted my 24v cluster. Into a 12 volt cluster. By removing the resistor and replacing it with a jumper wire to complete the circuit. And changed the Bulbs. U should be able to figure something out.
Maybe u can mod the board just would need to break the circuit

 

[bj40green]

Rudi, ever since I started selling the 12V cluster in my store, people have been regularly asking if I have a 24V cluster available. I don't believe it's available new; however, you stated that a 24V cluster is a 12V cluster with a resistor in the back and 24V bulbs. Is it straightforward to convert a 12V cluster to a 24V one? If so, which parts should be used? Thanks in advance.

Hi Racer,

Yes, the 12V and the 24V clusters are basically the same except for one track on the PCB. On the 12V it's one track and on the 24V it has a gap to divide the power into 2 circuits.
In short: The ammeter is the same
The fuel meter and sender are the same and get their power from the 30 ohm resistor
The temp meter and sender are the same. This circuit gets their power from the fuel meter.
The oil meter and sender are both 24V models.
All light bulbs (5x) have to be exchanged.
This picture shows it.

The gap in a 24V cluster

Conversion from 24V to 12V

The fuel meter has a build in Voltage regulator which provides the working voltage for itself and the temp meter.
The oil sender has a build in Voltage regulator. Why Toyota decided for a 24V stand alone circuit instead of a resistor is beyond me, but it should be possible to do the same with a resistor for this circuit. I have never tested this however.

Rudi

 

[bj40green]

So you need the 24V oil gauge #83510-60050 and 24V oil sender #83520-55020

Rudi

 

[78fj40mg]

You are awesome Rudi!!!

 

[Racer65]

Impressive post! Thanks Rudi. I think the only people who know more about these gauges are the Toyota engineers.

 

[bkdraft]

Tried to order a new speedo cable for my 68 FJ40, but was told by SOR that my speedo head does note exist, they only made two types, one the cable pushes on, the other held on with mail nut, mine is female. Any ideas on this one? I ended up modifying a nut to hold the cable onto the head.

 

[bj40green]

This is how a "screw on" cluster looks. Does yours look like this?

Rudi

 

[bkdraft]

The picture I posted is the back of my cluster, it does not look like yours. I used to see this type of speedo head back in the early 70's when I was a GM mechanic, mostly on old trucks.

 

[bj40green]

Can you post another picture but zoomed out, so that I can see more of the cluster?

Rudi

 

[bkdraft]

Dont have a picture right now, but the back looks very similar to the one you posted, but the speedo head is different

 

[bkdraft]

Here is picture of the face,